# JWT decoder

> Browser-only file conversion. Selected files are processed on this device and are not uploaded to a conversion server.

Source: https://localconverter.tech/decode-jwt

Inspect a JWT header, payload and expiry without asserting authenticity. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock. Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text.

## Useful tasks

- Read a JWT header and JSON payload during debugging.
- Compare expiry with the current computer clock.
- Inspect claims while keeping signature verification a separate step.

## Steps

1. **Provide the source**: Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text.  Read the operation note before starting, because supported syntax and file limits are part of the result contract. The original file is not overwritten or renamed by this workflow.
2. **Choose the intended result**: This operation uses a fixed report format, so no extra output configuration is required. Change settings according to the file or text you actually supplied. Defaults are a starting point rather than a promise that every source uses the same conventions. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.
3. **Create and inspect the output**: Use the main action button to run jwt decoder. Local processing checks the source and reports malformed or unsupported inputs. A completed job appears in Your results, with a download action and a preview when the output supports it. If the operation fails, read its message and correct the source or settings before retrying; changing only a filename does not change file contents.
4. **Save and verify the result**: Download the finished output and open it in the application or workflow that will consume it. Enter or upload the source, choose settings, then create and review your result. Check the values, layout, encoding or parsed structure relevant to your task. Keep the source when you may need another set of settings later. Temporary job downloads are session-owned and expire; saving your own copy is the way to retain a result.

## Settings


## Try jwt decoder with a small source

Try this source: eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJhbGljZSIsImV4cCI6MX0.abc. Use the initial settings, inspect the result and then change one setting to understand its effect. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.

## Check the result

Enter or upload the source, choose settings, then create and review your result. Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted. Open the saved output in the app or workflow where you plan to use it. Check one representative result before repeating the same settings with more files. The original files stay unchanged.

## Limits

- Files are processed on this device. Browser memory and engine-specific limits apply. Save results before reloading.
- Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted.
- Upload one file with a combined size of at most 100 MB. The completed output must fit within 200 MB.
- Pasted text and uploaded text have operation-specific UTF-8 byte limits. Productivity tools accept up to 1 MiB (1,048,576 bytes); non-ASCII characters can use several bytes each. If a file is selected, it takes priority over pasted text.
- Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first.

## Questions

### What does JWT decoder produce?

Inspect a JWT header, payload and expiry without asserting authenticity. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.

### Which source should I use?

Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. Supported file extensions are txt, md, markdown, json, csv, html, htm, css, js, sql, xml, yaml. The processing engine checks actual contents; a matching extension alone does not make malformed content valid.

### Why did this input fail?

Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted. Check syntax, required inputs and the ranges shown next to settings. An error keeps unsupported data from being presented as a successful conversion. Correct the source and retry rather than repeatedly resubmitting an unchanged invalid input.

### How should I check the download?

Enter or upload the source, choose settings, then create and review your result. Review the saved content in its destination application, including a typical case and any boundary values important to your use. A completed operation confirms processing finished; it cannot determine whether the supplied settings match your wider business requirements.

### Does JWT decoder upload files to another service?

Processing runs in this browser, on your device. Files and pasted input are not uploaded to a conversion server. The website and required engine assets must load first; large operations depend on available device memory.

### Can I continue after changing pages?

Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first.

## Related guides

- [Timestamp & timezone converter](https://localconverter.tech/convert-timestamp.md)
- [JSON difference checker](https://localconverter.tech/compare-json.md)
- [JSONPath explorer](https://localconverter.tech/query-json.md)
- [JSON to CSV](https://localconverter.tech/json-to-csv.md)
- [JSON to TSV](https://localconverter.tech/json-to-tsv.md)